Dozens of Dutch security officers, legal experts, diplomats and other civil servants were systematically spied on by Ukrainian and Russian intelligence services while probing the aftermath of the MH17 disaster, according to a report on Dutch television. Malaysia Airlines Flight 17, a scheduled passenger flight from Amsterdam to Kuala Lumpur, was shot down over eastern Ukraine on July 17, 2014. All 283 passengers and 15 crew on board, 196 of them Dutch citizens, were killed. In the aftermath of the disaster, the Dutch Safety Board spearheaded the establishment of the multinational Joint Investigation Team (JIT), which is still engaged in a criminal probe aimed at identifying, arresting and convicting the culprits behind the unprovoked attack on Flight MH17. As part of the JIT, dozens of Dutch officials traveled to Ukraine to initiate the investigation into the plane crash and repatriate victims’ bodies and belongings. Their activities were conducted with the support of the Ukrainian government, which is party to the JIT.

But on Tuesday, Holland’s RTL Niews broadcaster said that members of the Dutch JIT delegation were subjected to systematic and persistent spying by both Ukrainian and Russian government operatives. According to RTL, Dutch investigators found sophisticated eavesdropping devices in their hotel rooms in Ukraine, and believed that their electronic devices had been compromised. Citing “inside sources” from the Dutch government, the broadcaster said that, during their stay in Ukraine, members of the Dutch JIT delegation noticed that the microphones and cameras on their wireless electronic devices would turn on without being prompted. They also noticed that the devices would constantly try to connect to public WiFi networks without being prompted. Upon their return to Holland, Dutch officials had their wireless devices examined by Dutch government security experts. They were told that numerous malware were discovered on the devices.

RTL Niews said that the question of whether valuable information relating to the MH17 investigation was stolen by foreign spies remains unanswered. But it noted that the members of the Dutch JIT delegation were warned about possible espionage by foreign powers prior to traveling to Ukraine. During their stay there, they were not allowed to send messages in unencrypted format and were only permitted to hold sensitive conversations in especially designated rooms inside the Dutch embassy in Kiev. The Dutch government did not respond to questions submitted to it by RTL Niews. But it issued a statement saying that its security experts had briefed and trained the Dutch JIT delegation prior to its trip to Ukraine. Members of the delegation were told that foreign parties would seek to collect intelligence, because the MH17 investigation was taking place in a “conflict area with significant geopolitical interest” for many parties. They were therefore advised to “assume that they were being spied on [and] adjust [their] behavior accordingly” while in Ukraine, the Dutch government’s statement said.